Dual pump drive with overrunning clutches



Dec. 25, 1956 w. R. BATTEN ETAL 2,775,204

DUAL PUMP DRIVE WITH OVERRUNNING cw'rcass 2 Sheets-Sheet 1 Filed March23, 1953 I77 7/87) furs 9am 76. W

Dec. 25, 1956 W. R. BATTEN ETAL DUAL PUMP DRIVE WITH OVERRUNNINGCLUTCHES Filed March 23, 1953 2 Sheets-Sheet 2 Inflen/ors 7I'M, Z. W M MUnited States Patent DUAL PUMP DRIVE WITH OVERRUNNING CLUTCHES WebsterR. Batten and Donald Hadden, Rockford, Ill.,

asslgnors to Geo. D. Roper Corporation, Rockford, 111., a corporation ofIllinois This invention relates in general to a pump drive, and moreparticularly to a drive for driving a pair of pumps alternately from asingle hydraulic motor.

In the use of tank trucks for delivering two dilferent fuels it is, ofcourse, necessary to provide two separate pumps for pumping the fuels inseparate flows from the tank truck. For various reasons it has not beenfeasible to couple the two fuel pumps to the power takeofl shaft of thetank truck. Instead, it has been found to be more practical to drive thefuel pumps from an hydraulic motor arrangement operated by high pressurefluid from a control pump. The provision in such arrangements ofseparate hydraulic motors for each fuel pump has resulted in unnecessaryspace requirements and cost in such installations. These disadvantagesare avoided in the present invention by the provision of a drive for twofuel pumps which requires only a singlevmotor.

It is an object of the present invention to provide a novel and improveddrive for driving alternately a pair of pumps.

It is also an object of this invention to provide a novel and simplifiedarrangement for driving a pair of pumps alternately from a singlereversible motor.

The foregoing objects and advantages of the present mvention areaccomplished in the embodiment illustrated in the accompanying drawingby the provision of a pair of overrunning clutches in the drive from anhydraulic motor to a pair of pumps, these overrunning clutches servingto impart the drive to one of the other of the pumps, depending on thedirection of the motor drive.

Other and further objects and advantages of the present invention willbe apparent from the following description of one embodiment of theinvention, illustrated in the accompanying drawing.

In the drawings:

Figure 1 is a perspective view, with parts broken away, showing thenovel drive of the present invention from a single hydraulic motor to apair of rotary pumps intended to be driven alternately;

Figure 2 is an enlarged perspective view showing the ovenrunningclutches in the drive from the hydraulic motor, the motor operating inthe reverse direction from its operation in Fig. 1;

Figure 3 is a schematic diagram showing the hydraulic circuit fordriving the hydraulic motor in the present assembly, with the controlvalve shown in enlarged longitudinal section in one of its extremepositions for causing the hydraulic motor to be driven in one direction;and

Figure 4 is a view similar to Fig. 3, but with the control valvepositioned to reverse the hydraulic motor.

Referring to the drawings in Fig. 1 there is shown a conventionalhydraulic motor of the gear type having a pair of meshing gears 11 and12 adapted to be rotated by the pressure of the incoming fluid, such asoil. In Fig. l, the arrows indicate that the pressure fluid passesthrough pipe 13 into the motor chamber 14 at a location therein betweenthe meshing gears, causing the gears to rotate in the directionindicated. The fluid then passes 2,775,204 Patented Dec. 25, 1956 out ofthe motor chamber through the pipe 15. The pressure fluid for thehydraulic motor is supplied from a sump by means of a pump 41 and thencethrough the control valve, indicated generally at 42 in Fig. 1. From thehydraulic motor 10 the pressure fluid passes back through the controlvalve 42 to the sump. On tank trucks, the pump 41 would ordinarily bedriven from the power take-oil shaft on the truck.

The control valve 42 is shown in detail in Figs. 3 and 4 and isconstructed to pass fluid under pressure to either side of the hydraulicmotor 10, or to block the flow of fluid to the motor, so that therotation of the motor may be selectively controlled by means of thevalve 42. This valve 42 is of conventional construction and includes ahousing 43 having an inlet passage 44 which receives oil under pressurefrom the pump 41 and an outlet passage 45 which leads through returnconduit 46 back to the sump 40. The valve housing 43 is formed with aninternal chamber 47 communicating with the outlet passage 45 and withinwhich is located a valve body 48. The latter is formed with an inletpassage 49 leading from the inlet 44 in the valve housing to a pair ofbranch passages 50 and 51 in the valve body. The branch passage 50 leadsto a restricted cylindrical passage 52, which communicates at its otherend with a chamber 53 in the valve body. Chamber 53 communicates with apassage 54 in the valve housing which communicates at its other end withthe conduit 13 leading to one side of the hydraulic motor 10. In likemanner, the other branch inlet passage 51 in the valve body leads to arestricted cylindrical passage 55 leading to a chamber 56 in the valvebody, this chamber in turn communicating with a passage 57 in the valvehousing connected to the conduit 15 at the other side of the hydraulicmotor 10. A restricted cylindrical passage 58, of the same size as thepassage 52, extends from the opposite end of chamber 53 and in alignmentwith passage 52 and communicates with the chamber 47 in the valvehousing. In like manner, a similar passage 5% extends from the oppositeend of the valve body chamber 56 in alignment with the restrictedcylindrical passage 55 and communicates with the valve housing chamber47. A chamber 60 is formed centrally in the valve body 48 and incommunication with the valve housing chamber 47. A pair of alignedrestricted cylindrical passages 61 and 62 extend between the chamber 60and the branch inlet passages 50 and 51, respectively.

For controlling the various flows through the valve there is provided areciprocable stem 63 which carries a first cylindrical plug 64 adaptedto be snugly disposed within preselected ones of the valve body passages58, 52, and 61, depending upon the axial position of the valve stem. Thevalve stem also carries a middle plug 65 adapted to be disposed snuglyin either the passage 61 or the passage 62, to selectively block eitherof these passages from communication with the respective branch inletpassage 50 or 51. At its inner end the valve stem carries a third plug66 adapted to be snugly disposed within preselected ones of the passages62, 55 and 59. The valve stem at its outer end is pivoted at 67 to amanually controlled operating lever 68, which is pivotally mounted at 69at its lower end on a bracket 70' fastened to the valve housing. Asuitable O-ring seal 71 is provided on the valve stem to prevent leakagethereat.

In the operation of this control valve, when it is desired to drive themotor in the direction shown in Figs. 1 and 3, with hydraulic liquidbeing supplied under pres sure to the conduit 13, the operating lever ispulled outwardly, as shown in Fig. 3, to pull the valve stem 63 to oneextreme position. In this position, plug 66 is disposed snugly withinthe valve body passages 55 and 62, to thereby block communicationbetween the branch inlet 51 and the valve body chambers 56 and 60. Plug65 is snugly disposed within the valve body passage 61, thereby blockingcommunication between branch inlet 50 and the valve body chamber 60.Plug 64 is disposed in valve body passage 58 and blocks communicationbetween the valve .body chamber 53 and the valve housing chamber '47.Oil under pressure .flows from pump 41 through inlets 44 and 49, branchinlet 50, passage 52, valve body .chamber 53, passage 54 and conduit 13to one side of the hydraulic motor 10. .After passing through the motorthe oil is exhausted back to the sump 41) through con- :duit 15, passage57, valve body chamber 56, passage 59, valve housing chamber 47, outletpassage 45 and return conduit 46.

To reverse the direction of the motor, the valve lever 68 is movedinwardly to move the valve stem 63 in the same direction to its otherextreme position (Fig. 4). in this position, plug 66 is disposed snuglywithin valve body passage 59 to thereby block communication between thevalve body chamber 56 and valve housing chamber 47. Plug 65 is .snuglydisposed within valve body passage 62, thereby blocking communicationbetween the branch inlet 51 and the valve body chamber 611. Plug issnugly disposed within the valve body passages 61 and 52, and blockscommunication between the branch inlet50 and the valve body chambers 60and 53. Therefore, oil under pressure from pump 41 flows through inletpassages 44 and 49, branch inlet 51, passage 55, valve body chamber 56and passage 57 to the conduit 15 leading to one side of the hydraulicmotor 1%. After passing through the hydraulic motor to drive it in theopposite direction from Fig. 3, the oil passes through conduit 13,passage 54, valve body chamber 53, passage '58, valve housing chamber47, outlet passage 45 and return conduit 46 to the sump 40.

To stop the hydraulic motor 10, the valve stem may be positioned in aneutra position intermediate its extreme positions. In this position,the plug 65 is disposed within the central chamber 60 in the valve bodyand neither of the valve body passages 61 and 62 is blocked. Therefore,oil under pressure flows through the branch inlets 50 and 51 and thencethrough the valve body passages 61 and 62 into the valve body chamber60, and from there to the valve housing chamber 47, from which itreturns through outlet passage 45 and return conduit 46 to the sump 40without actuating the fluid motor 10. In this neutral position, bothplugs 64 and 66 block the respective passages 52 and 55, so that no oilflows to the hydraulic motor in either direction.

Returning to the product pump drive system shown in Fig. l, the uppergear 11 of the motor is attached to a rotary shaft 16, which projectsfrom one face of gear 11 out through the end wall 17 of the motorhousing, being supported for rotation thereat by a bearing bushing 18.In like manner, rotary shaft 19 connected to the upper gear 11 of thehydraulic motor projects out through the .opposite end wall of the motorhousing.

Referring to Fig. 2, the outer end of motor shaft 16 abuts against theouter end of the drive shaft 21) of a conventional first gear pump 21(Fig. 1). The drive shaft 20. is connected to the drive gear 22 of thepump 21, which meshes with a driven gear 23 to draw in fluid from theinlet pipe 24 and discharge the fluid under pressure to the outlet pipe25.

.To couple the motor shaft 16 to the pump shaft there is provided aconventional overrunning clutch in the form of a tightly wound helicalspring 26. This spring is composed of wire of square cross-section andis fitted closely over the adjacent ends of the abutting shafts 16 and21) to normally grip both shafts tightly. Due to the direction of thehelical wrap around of spring 26, when motor shaft 16 is drivencounterclockwise in the drawing it causes the spring 26 to wind itselftightly onto the shafts 16 and 20. This locks the pump shaft 20mechanically to the motor shaft 16, so that the first pump 21 is driven,

from hydraulic motor 10 in this direction of rotation of motor shaft 16.When hydraulic motor 10 is reversed, by reversing the pressure fluidinlet and outlet connections to the hydraulic motor, the direction ofrotation of motor shaft 16 is correspondingly reversed. When rotated inthis reverse direction, shaft 16 causes the helical spring 26 to unwindand expand, thereby becoming loosened from the drive shaft 20 for pump21, so that very little driving force, or none at all, is imparted tothe pump drive shaft 20.

In similar fashion, the free end of the other motor shaft 19 abutsagainst the drive shaft 27 for a conventional second gear pump 28 havingthe suction inlet conduit 30 and the discharge conduit 31. Anoverrunning clutch 29 in the form of a tightly wound, square wire,helical spring couples the motor shaft 19 to the pump shaft 27. Thespring 29 is fitted closely onto the shafts 19 and 27 to normally gripboth tightly.

When motor shaft 19 is driven counterclockwise in the drawing (at whichtime the other motor shaft 16 is driven in the same direction to drivethe first pump 21), the clutch spring 29 is caused to unwind and expand,thereby becoming loosened from the drive shaft 27 for the second pump28. Thus, no drive is imparted from motor 10 to the second pump 28 whenthis motor is driving the first pump 21.

Conversely, when motor shaft 19 is driven clockwise in the drawing, asshown in Fig. 2 (at which time no drive is imparted from the motor tothe first pump 21), the clutch spring 29 is caused to wind tightly aboutthe shafts 19 and 27, coupling them together mechanically to impart thedrive from motor 10 to the second pump 28. Thus, when the motor drivesthe second pump 28 it is disconnected from driving relation with thefirst pump 21.

From the foregoing it will be apparent that the present inventionprovides a novel and simplified arrangement for driving two pumpsalternately. Only a single reversible driving motor is required, and theselection of the pump to be driven is controlled simply by choosing thedirection in which the driving motor operates, the overrunning clutchesoperating automatically as described to impart the drive from the motorto only the desired one of the pumps, without driving the other pump atthe same time.

For the purpose of illustrating the present invention, there has beendescribed and shown in the accompanying drawing a specific preferredform thereof. However, it is to be understood that the invention issusceptible of other and different embodiments from that shown herein.For example, the hydraulic gear type motor might be replaced by a vanemotor or other type of driving motor, the helical spring typeoverrunning clutches may be replaced by overrunning clutches of othertypes capable of functioning successfully in the combination of'thepresent invention, and pumps of other types adapted to be'driven fromrotary drive shafts may be substituted in place of the gear pumps shownand described herein. Therefore, it is to be understood that variousmodifications, omissions and refinements which depart from the describedform of the invention may be adopted without departing from the spiritand scope of the present invention.

We claim: I

'1. A pumping apparatus comprising a rotary hydraulic motor having firstand second fluid passages communb cating therewith, first and secondrotary shafts driven in unison by said motor, a first rotary pump havinga drive shaft, 21 second rotary pump having a drive shaft, a firstoverrunning clutch means disposed between said first shaft and the driveshaft for said first pump for establishing a driving connectiontherebetween when said motor rotates in one direction, a secondoverrunning clutch means disposed between said second shaft and thedrive shaft for said second pump for establishing a driving connectiontherebetween when said motor rotates in the other direction, and controlvalve means connected to said first and second fluid passages of saidmotor for selectively passing fluid in either direction to said motor tocontrol the direction of rotation of said motor and thereby selectivelydrive said first or said second pump, said control valve means includingvalve means operative to block the flow of fluid to and from said firstand second passages to thereby lock said motor against rotation ineither direction and prevent reverse rotation of said first and saidsecond pumps.

2. A pumping apparatus comprising a rotary hydraulic motor having firstand second fluid passages communicating therewith, first and secondrotary shafts driven in unison by said motor, a first rotary pump havinga drive shaft, a second rotary pump having a drive shaft, a firstoverrunning clutch means disposed between said first shaft and the driveshaft for said first pump for establishing a driving connectiontherebetween when said motor rotates in one direction, a secondoverrunning clutch means disposed between said second shaft and thedrive shaft for said second pump for establishing a driving connectiontherebetween when said motor rotates in the other direction, and acontrol valve means connected to said first and second fluid passages ofsaid motor, said control valve means being operable in a first positionthereof to pass fluid under pressure into said first passage and out ofsaid second passage to rotate said motor in one direction and drive saidfirst pump, said control valve means being operable in a second positionthereof to pass fluid under pressure into said second passage and out ofsaid first passage to rotate said motor in the other direction unison bysaid motor, a first rotary pump having a drive shaft, a second rotarypump having a drive shaft, a first overrunning clutch means disposedbetween said first shaft and the drive shaft for said first pump forestablishing a driving connection therebetween when said motor rotatesin one direction, a second overrunning clutch means disposed betweensaid second shaft and the drive shaft for said second pump forestablishing a driving connection therebetween when said motor rotatesin the other direction, a drive pump for said motor, control valve meansconnected to said drive pump and to said first and second fluid passagesof said motor, said valve means being operable in a first positionthereof to pass fluid under pressure from said drive pump into saidfirst passage and out of said second passage to rotate said motor in onedirection and drive said first pump, said control valve means beingoperable in a second position thereof to pass fluid under pressure fromsaid drive pump into said second passage and out of said first passageto rotate said motor in the other direction and drive said second pump,said valve means being operable in a third position thereof to by-passthe fluid. discharged from said drive pump back to the inlet thereof andto block the flow of fluid to and from said first and second passages tolock said motor against rotation in either direction and prevent reverserotation of said first and second pumps.

References Cited in the file of this patent UNITED STATES PATENTS353,564 Kamm et al Nov. 30, 1886 899,513 Champ Sept. 29, 1908 952,613Fairweather et a1 Mar. 22, 1910 1,557,222 Warner Oct. 13, 1925 2,390,204Curtis Dec. 4, 1945 2,603,157 Conery July 15, 1952 2,643,614 RosenkrausJune 30, 1953

